Sub-Saharan Africa (SSA) faces significant challenges in food security, with an expected threefold population increase by 2100 and agricultural productivity failing to keep pace. This is largely due to unfavorable climate change, poor soil fertility, continuous cultivation, and pathogen pressure, particularly plant-parasitic nematodes (PPNs). Yam, a vital staple crop in West Africa, suffers substantial yield and post-harvest losses (17-50%) due to PPNs, especially *Scutellonema bradys*. Current control options are often unavailable or unaffordable for smallholder farmers, who constitute about 80% of the SSA population. Early PPN protection via seed treatment is crucial; however, cost-effective, biodegradable delivery systems are needed. Previous research demonstrated the potential of paper-like matrices from banana waste for controlled release of small molecules. This study explores the use of these matrices, enhanced with recycled corrugated cardboard, as biodegradable seed wraps for yam seed pieces, aiming to provide sustainable and affordable nematode control.

The literature extensively documents the impact of plant-parasitic nematodes on yam production in sub-Saharan Africa, highlighting significant yield losses and post-harvest challenges. Existing nematode control methods are often limited by cost, accessibility, and environmental impact. Research on biodegradable and sustainable materials for controlled release of pesticides and other agricultural inputs is growing, with studies demonstrating the potential of various plant-based materials. This paper builds upon previous work showing the promise of banana fiber-based matrices for targeted delivery of small molecules. The use of recycled cardboard is also explored as a cost-effective and readily available material to improve matrix strength and release properties.

Biodegradable matrices were created using banana fiber (BF) and recycled old corrugated cardboard (OCC) in various proportions, without chemical additives. The structure and composition of the resulting hybrids were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Biodegradability was assessed by incubating the matrices in soil with a growing tomato plant. The interaction between the matrices and abamectin (Abm), a nematicide, was investigated through water sorption studies and isothermal titration calorimetry (ITC). Pilot-scale production of a suitable matrix (BF:OCC ratio of 80:20) was achieved using a Fourdrinier paper machine. Field trials were conducted over four years (2015-2018) in three Benin districts, comparing yam yields and quality using Abm-loaded banana paper (BP-Abm), untreated banana paper (BP), and farmers' practice (FP). Nematode populations in tuber peels were assessed at harvest and after 3 and 5 months of storage. Farmers' and consumers' perceptions of the technology were also evaluated. Statistical analyses including one-way ANOVA and Waller-Duncan K-ratio t-test were used to analyze the data.

Hybrid matrices of banana fiber and recycled cardboard exhibited tunable strength and Abm release profiles. Higher BF content resulted in faster water flow and Abm diffusion, while higher OCC content increased strength and Abm binding. The BF:OCC (80:20) hybrid showed a balance between biodegradability, Abm release, and strength, making it suitable for field trials. Field trials demonstrated a significant increase in yam yield (28-57% with BP-Abm and 27-53% with BP) compared to FP across all years, with greater yield increases observed during drier seasons. The BP-Abm treatment consistently resulted in a considerable reduction (80%) in final yam nematode populations in tuber peels. After 3 and 5 months of storage, W&P-treated tubers showed significantly lower nematode populations, less weight loss, and reduced dry rot and cracking compared to FP. Economic analysis showed higher cost-profit ratios and net margins for W&P treatments. Farmers and consumers expressed strong preference for yams produced using the W&P technology, particularly BP-Abm, due to superior quality and appearance.

The findings strongly support the effectiveness of the plant-biomass-based hybrid seed wraps as a sustainable and cost-effective method for enhancing yam production and reducing post-harvest losses in SSA. The combination of nematode control and improved tuber quality significantly contributes to increased yields and economic benefits for smallholder farmers. The tunable nature of the seed wraps allows for potential applications beyond nematode control, such as delivering other crop production moieties (e.g., nutrients, biologicals). The success of this technology highlights the importance of integrating sustainable materials and environmentally friendly practices in addressing food security challenges in developing countries. The observed correlation between rainfall and yield differences suggests the need for further research to optimize Abm application timing and concentrations.

This study successfully developed a sustainable and scalable seed wrap technology using readily available and cost-effective plant biomass and recycled materials. Field trials confirmed its effectiveness in increasing yam yields, improving tuber quality, and reducing post-harvest losses. The technology’s versatility and positive farmer and consumer acceptance suggest significant potential for widespread adoption in SSA and other regions. Future work could explore modifications for improved scalability and delivery of other essential agricultural inputs.

The study focused on a specific region and crop; therefore, the generalizability of the findings to other regions or crops may need further investigation. While the use of ultra-low volumes of Abm minimizes environmental impact, potential effects on non-target organisms warrant further study. The impact of variations in rainfall patterns on treatment effectiveness should also be further analyzed. Additional research could explore potential long-term environmental effects of the biodegradable materials.